In the loading and unloading of trucks, a ramp is often used to span the distance from the truck trailer to the ground surface. Similarly, a ramp is also used to span the distance from a dock surface to the ground surface. These ramps allow, for example, the trailer to be unloaded by providing a walking surface from the trailer down to the ground. The surface of the ramp also allows unloading dollies or hand-trucks to be used in unloading the contents of the trailer.
Some truck trailers are specially equipped to transport a variety of items requiring different storage temperatures. For example, truck trailers known as “multi-temp” trailers may be equipped with non-refrigerated, refrigerated and freezer compartments. Each of these compartments must be equipped with an access area for loading and unloading. This access area is typically provided in the form of a door located on the side of the trailer. A ramp is often used to span the distance from each of the side doors down to the ground surface. In using a ramp to unload these trailers, it is sometimes necessary to move the ramp from one side door to another as the various compartments are unloaded. Trailers can also be provided with an access door at the rear of the trailer for loading and unloading.
Historically, prior art ramps are unitary, rigid structures that have lengths sufficient to span the distance from the trailer surface to the ground at an angle that allows the trailer to be unloaded safely and comfortably. Prior art ramps have addressed some of the problems associated with unitary, rigid ramps by incorporating a hinge to allow the ramp to fold into a more compact position for stowing. See for example U.S. Pat. No. 6,536,064 and U.S. Provisional Application No. 61/584,116, the entirety of which are herein incorporated by reference. While an improvement, folding ramps have drawbacks. For example, lifting a section of the ramp and rotating it about a pivot point can require a great deal of strength. The potential energy contained in a folding ramp, when it is at its highest point during unfolding, makes the ramp dangerous to nearby people and things. Further, maneuvering a ramp with a hinged axis at or near its midpoint can be awkward and/or dangerous due the possibility of pinched fingers.
There is a need in the art for a product that addresses these and/or other issues and shortcomings of the prior art.